Apparatus for preventing tangle of endless rope in mining or sea life gathering

ABSTRACT

Apparatus for preventing tangling of an endless rope continuously lowered from, and raised onto, a ship moving in water, including placing inclined resistance plates or other materials having the same effect on the endless rope at suitable intervals to increase the distance of separation of the descending part and the ascending part of the rope from each other by the force of the water produced by the forward movement of the ship on the resistance plates. The endless rope is provided with either buckets for mining of minerals from the sea bottom or with nets for catching sea life.

United States Patent 1191 Masuda [451 Sept. 30, 1975 [76] Inventor:Yoshio Masuda, Kohdan Jutaku 31-1, 10-1, Tamadaira 4-chome, Hino, Tokyo,Japan [22] Filed: Dec. 27, 1973 211 App]. No.: 428,834

[56] References Cited UNITED STATES PATENTS 879,863 2/1908 Gladding43/6.5 2,316,463 4/1943 Skulina i. 198/151 X 3,297,303 1/1967 Aizawa254/138 3,401,859 9/1968 Rienks 226/196 3,410,014 11/1968 Jenssen 43/93,672,079 6/1972 Masuda et a1. 37/69 3,675,348 7/1972 Dane, Jr. 37/693,713,301 1/1973 Bryant 226/187 X 3,766,671 10/1973 Guntert 37/69FOREIGN PATENTS OR APPLICATIONS 22,037 2/1912 Norway 43/13 1,239,1787/1971 United Kingdom.... 37/69 999,968 7/1965 United Kingdom....254/137 80,446 7/1952 Norway 43/6.5

Primary E.\'amilzerClifford D. Crowder Attorney, Agent, or FirmFidelman,Wolffe & Leitner 1 1 ABSTRACT Apparatus for preventing tangling of anendless rope continuously lowered from, and raised onto, a ship movingin water, including placing inclined resistance plates or othermaterials having the same effect on the endless rope at suitableintervals to increase the distance of separation of the descending partand the ascending part of the rope from each other by the force of thewater produced by the forward movement of the ship on the resistanceplates. The endless rope is provided with either buckets for mining ofminerals from the sea bottom or with nets for catching sea life.

9 Claims, 22 Drawing Figures US. Patent Sept. 30,1975 Sheetlofll3,908,291

US. Patent Sept. 30,1975 SheetZofll 3,908,291

U.S. Patent Sept. 30,1975 Sheet3of11 3,908,291

U.S. Patent Sept. 30,1975 Sheet40f1l 3,908,291

US. Patent Sept. 30,1975 Sheet5of11 3,908,291

US. Patent Sept. 30,1975 Sheet6of11 3,908,291

Fl G.l2 F l 613 U.S. Patent Sept. 30,1975 Sheet7ofl1 3,908,291

U.S. Patent Sept. 30,1975 Sheet8ofl1 3,908,291

US. Patent Sept. 30,1975 Sheet9ofll 3,908,291

I50 H6 [5| I48 H5 I49 US. Patent Sept. 30,1975 Sheet 10 ofll 3,908,291

F Iv 6.20

07 L buzz l I I07 US. Patent Sept. 30,1975 Sheet 11 ofll 3,908,291

FIG.22

APPARATUS FOR PREVENTING TANGLE OF ENDLESS ROPE IN MINING OR SEA LIFEGATHERING SUMMARY OF THE INVENTION This invention relates to the methodof preventing the tangle of the descending part and the ascending partof an endless rope which has been apt to happen before and the mechanismtherefor. The endless rope is moving in water. As described in US. Pat.No. 3,672,079, the rope is continuously drawn down into the sea from aship at a certain speed and pulled up to the ship at the same speedcirculating in the ropes axial direction, and the rope also moves indirection transverse to the axis of the rope. According to thisinvention, continuous mining of metallic nodules like manganese nodulesfrom the deep sea-bottom as described in the said US. patent can besafely done. Other practical effect of the wide application of thepresent invention can be displayed by applying it, for example, tocontinuously catching sea life with nets.

The present inventor has done several tests concerning the invention ofthe said US. patent. In the southeast Hawaii in summer, 1972, tests wereperformed using the Dai-ni Kyokuyo-Maru ship (17,000 t) at the sea of4,700 m depth to mine a large quantities of metallic nodules from thedeep sea-bottom for the first in the world. Simultaneously withfavorable results many problems to solve including the rope tangleproblem were also found through the test.

If an endless rope of about 15,000 m length is extended from both endsof a ship of about 150 m length and drags on the sea-bottom of 5,000 mdepth, the ratio of the width between two rope lines to the half lengthof the rope is 1:50 and the rope forms a loop having a very narrowwidth. In the said test using the Dai-ni Kyokuyo-Maru ship, the ropetangle accident happened about three times. One of the reasons for thetangling is the sudden stopping of circulation of the rope i.e., themovement of the rope in the ropes axial direction. However the mostbasic reason for the tangling resides in that the two rope lines,descending part and ascending part, are too close to each other.

In order to prevent the rope tangle, there are some suggestions. One isto use a special large ship of more than 300 m length, and the other isto use two ships. In the latter suggestion, two ships are separatedquite a distance from each other and a rope loop is extending betweenthe two ships, i.e., a rope is falling to the sea from one ship and ispulled up to another ship. These suggestions are possible, but it isstrongly required to use a normal size ship because of the cost, andother reasons.

The object of this invention is to provide the mechanism meeting theserequirements. First the shape of the rope line in a water tank wasstudied in the several test of the continuous mining mechanism.Thereafter this invention was completed by attaching resistance platesto the endless rope at suitable intervals so that the descending partand the ascending part of the rope are automatically separated from eachother by the water flow acting on the resistance plates while the ropeis moving. According to this invention, a normal size ship is ofsufficient width to provide enough distance between two rope linessimilarly to the case of using a special large ship or two ships.Moreover in the mechanism using one ship, it is possible to draw downand pull up the rope only at the rear part of the ship; i.e., it is notnecessary to use both front and rear parts of the ship. This is one ofthe features of this invention.

As the second feature of this invention, this invention is employing aspecial driving unit for the endless rope allowing the buckets and theresistance plates to be driven safely and smoothly.

According to this invention, it is needless to say that metallic noduleslike manganese nodules, etc. can be continuously mined from the deepsea-bottom. Besides it is also possible to catch sea life with netscontinuously and economically. Furthermore many other applications canbe expected. This invention can display its features mainly in a normalsize ship, including the feature of easy movement of the ship byextending the rope only from the rear part.

BRIEF DESCRIPTION OF THE DRAWINGS Accompanying drawings show someexamples embodying the present invention.

FIGS. 1 to 16 relate to a mechanism for continuously mining metallicnodules from the deep sea-bottom;

FIG. 1 illustrates the general arrangement of the said mechanism;

FIG. 2 is an explanatory view showing one example of the bucket actingto increase the distance between two rope lines;

FIGS. 3 and 4 are explanatory views for showing that a bucket generatesthe force to increase the distance between two rope lines;

FIGS. 5 to 9 relate to a test using a water tank;

FIG. 5 illustrates the general arrangement of the mechanism tested inthe water tank;

FIG. 6 shows the rope loop shape of the case the rope is drawn in waterunder the condition the rope is not circulating;

FIG. 7 shows where the case the rope is drawn in water while the rope iscirculating;

FIG. 8 shows where the case the circulating speed of the rope is thesame as or lower than the speed of the carriages movement while the ropeis dragging on the tank bottom;

FIG. 9 shows where the case the circulating speed of the rope is thesame as or higher than the speed of the carriages movement while therope is dragging on the tank bottom;

FIG. 10 is a view for explaining the condition where the distancebetween two rope lines is increased according to the effect of thepresent invention;

FIGS. 11 to 13 relate to a driving system of the present invention;

FIG. 11 is a view for explaining a driving system provided on the ship;

FIG. 12 is a front elevation view of a ball roller of the drivingsystem;

FIG. 13 is a side elevation view of the same;

FIGS. 14 to 16 show another example embodying the present invention;

FIG. 14 is an explanatory view showing where a resistance plate actingto increase the distance between two rope lines is attached to a rope;and

FIGS. 15 and 16 are explanatory views showing the action of theresistance plate to increase the distance between two rope lines.

FIGS. 17 to 23 relate to a mechanism for continuously catching sea lifeusing nets;

FIG. 17 is a perspective view showing the condition of catching sealife;

FIG. 18 is a perspective view showing the condition of attaching a netto the rope;

FIG. 19 is a perspective view showing the condition of attaching aresistance plate to the rope;

FIG. 20 is an explanatory perspective view showing the effect of theresistance plate;

FIG. 21 is a front elevation view of a driving system;

FIG. 22 is a side elevation view of the same; and

DETAILED DESCRIPTION OF THE INVENTION Some examples embodying thepresent invention will be explained hereinbelow in conjunction withaccompanying drawings. FIGS. 1 to 16, which relate to one embodiment ofthe present invention, show a mecha nism for continuously miningmetallic nodules from the deep sea-bottom. In FIG. 1, a mining ship 1has a propeller 2 for forward and rearward movement, a frontside-thruster l8 and a rear side-thruster 19 for controlling the speedof the traverse movement, a front guide wheel equipment 3, a rear guidewheel equipment 4, and ball rollers 5, 6, 7 and 8 for driving an endlessrope (mining rope) R. The endless rope R has a loop shape consisting ofa descending part 9 falling from the rear guide wheel equipment 4 to thesea, a part 10 at the sea-bottom, an ascending part 11 to be pulled upto the front guide wheel equipment 3, and a part 12 on the ship to bedriven by the ball rollers 5, 6, 7 and 8. A number of buckets B areattached to the endless rope R, i.e., buckets 13, 14, l5, l6 and 17 areattached to each part 9, 10, 11 and 12 of the rope R respectively atregular intervals. The bucket B is used to collect metallic nodules fromthe sea-bottom and pulled up to the ship 1 by means of the rope R.During the normal mining operation, the bucket 13 of the descending rope9 is empty, the bucket 14 of the rope 10 is placed at the sea-bottom andthe bucket 15 dredges on the seabottom surface to collect metallicnodules. The bucket 16 of the ascending rope 11 contains metallicnodules. At the front guide wheel equipment 3, the mouth of the bucket16 turns downward by the arrangement of the guide wheels, thereby thenodules are dropped onto the ship. The rope 12 on the ship passesthrough the ball rollers 5, 6, 7 and 8 together with the hanged bucket17.

As shown in FIG. 2, the rope R (descending part 9 in the drawing) hasfixing metals 20 and 21 and 22 and 23 respectively at certain intervalsto fix the position of the slip rings 24 and 25 relative to the ropewhile allowing the bucket B to rotate around the rope. The front slipring 24 has a front rod 26 for hanging the bucket, and the rod 26 has afront short arm rod 27 and a front long arm rod 28 connected to frontcorner hooks 37 and 38 of the bucket respectively. In the same mannerthe rear slip ring 25 has a rear rod 29 for hanging the bucket and therod 29 has a rear short arm rod 30 and a rear long arm rod 31 connectedto rear corner hooks 39 and 40 respectively. Meanwhile the bucket B hastop planar plate (a resistance plate) 32, a side net 33, a bottom net34, a side net 35 and a back net 36 and its weight is properlyregulated.

It is one of the main feature of this invention that the bucket B ishanged from front and rear sides in its inclined manner by thedifference of the length of the short arm rod and the long arm rod. Anorthogonal X, Y, Z is shown in FIG. 2 to illustrate that the line 9 isslightly inclined relative to the Y and Z axis. The short and long frontand rear arm rods incline the bucket B relative to the X and Z axis.Thus, the plate is inclined to all three axis. As illustrated in FIGS. 3and 4, the top planar plate 32 is inclined at equal but opposite angles411 and 41', respectively, with respect to a plane perpendicular tofront and rear rods 26 and 29. With reference to the coordinates of FIG.2, plate 32 of FIG. 4 forms substantially the same angles with respectto Y and Z axis, but forms the same angle with respect to the X axis.The Y axis is perpendicular to the surface of the water, the Z axis isparallel to the movement of the ship and the X axis is perpendicular tothe movement of the ship.

It is a well-known technique that in the method of trollfishing, inorder to open the mouth of a troll net, resistance plates called otterboard" are fitted to both sides of the mouth to get the outward force byutilizing the flow resistance force. However, the normal otter board isnot suitable to a circulating rope because the endless rope R of theloop shape having a number of buckets B makes a circulating motion whichis not found in the static troll net. In the present invention, thebuckets B are hanged from their front and rear sides with the rear sideof the bucket B is closer to the ship at the descending rope, and at theascending rope the front side of the bucket B is up-side (closer to theship). That means the inclination of the bucket B at both lines of therope R is opposite to each other as observed from the ship.

In FIG. 3, the bucket 13 is hanged from the descend ing rope 9 (which ismoving up at a right angle to the surface of the paper) with someinclination 41 by means of the rear slip-ring 25, rear hanging rod 29,rear short arm rod 30 and rear long arm rod 31. Therefore water flow 42,produced by the movement of the boat passes through the side net 33,bottom net 34 and side net 35, and acts on the top plate (resistanceplate) 32, so that the water flow 42 generates thrust 43 in thedirection of the water flow and transverse thrust 44 which is directedat a right angle to the direction of the thrust 43 and which increasesthe distance between the descending rope 9 and the ascending rope 11.Since the angle which the rope 9 makes with respect to the X axis or thevertical is relatively small, the force produced by the bucket movingdown into the water is minimal and thus can be ignored.

In FIG. 4, the bucket 16 is hanged from the ascending rope 11 (movingdownward at a right angle into the paper) with some inclination 41contrary to in FIG. 3 by means of the front slip ring 24, front hangingrod 26, front short arm rod 27 and front long arm rod 28. Therefore thewater flow 42 acts on top planar plate (resistance plate) 32, andgenerates thrust 45 in the direction of the water flow and transversethrust 46 which is directed at a right angle to the direction of thethrust 45 and which increases the distance between the descending rope 9and the ascending rope 11.

As these thrust forces made by the water flow are not so large incomparison with the buckets weight, they do not affect the buckethanging condition. Moreover, as the bucket is hanged from front and rearsides in parallel with the rope line, the flow resistance generated bythe driving speed of the rope is relatively small. It is also one of thefeatures of this invention.

How much such outward forces affect the loop shape of the rope in waterand how the rope moves in water will be explained hereinbelow on thebasis of the test using a huge water tank. The test was done on a scaleof 1:2000 of the previous test carried out off Hawaii. In FIG. 5, anascending part 50, a part 51 at the tank bottom and a descending part 52of a rope R form a loop shape. The rope R'is hanged from a driving wheel48 and has many small lead weights B at certain intervals instead of thebucket B. An arm 49 is turned by a man 56 so that the driving wheel 48can circulate the loop of the rope R. A man can move on the tank byriding on a carriage 53. In the test, water depth 47 of the water tankbetween water surface 54 and tank bottom 55 was about 2.25 m and thelength of the rope was about 6 m.

As the result of the test, when the loop of the rope R is drawn in waterin the direction of arrow 59 by moving the carriage 53 under thecondition the rope is not circulating, the ascending rope 50 and thedescending rope 52 extend straightly almost in parallel with each otherand have no difference on the inclination thereof as shown in FIG. 6.However after the rope R has begun to circulate, when the whole loop ofthe rope R is drawn in water in the direction of the arrow 59 as theascending rope 50 is pulled up and the descending rope 52 is drawn down,an inclining angle 57 of the ascending rope 50 relative to vertical,increase to become larger than a decreased inclining angle 58 of thedescending rope 52 relative to vertical as shown in FIG. 7. Thereby thedifference of high-and-low occurs between both parts 50 and 52 of therope R and the descending part 52 becomes lower. However, the approachof both parts 50 and 52 can not be found except at the end of the loop.

The above-mentioned is the case the loop of the rope R is drawn in waterwithout touching the tank bottom. In case the rope R circulates as therope touches the tank bottom by extending the rope and reducing thedrawing speed of the rope, when the circulating speed 60 of the rope Ris equivalent to or slower than the drawn speed 59 of the carriagesmovement, the shape of the loop in water and at the tank bottom is asshown in FIG. 8. That is the rope 51 is placed properly on the tankbottom 55 and is pulled up dredging the bottom. It was proved that therope tangle seems not to occur in the condition of FIG. 8.

When the circulating speed 60 of the rope R is higher than the drawingspeed 59 of the carriages movement, the shape of the loop in water andat the tank bottom 55 is as shown in FIG. 9. In this case, as the rope51 subsequently placed on the tank bottom 55 moves zigzag and changesits position, the ascending rope 50 tangles with the following rope 51in an extreme case. When the rope with the buckets B hanged is fallingto the sea-bottom at high speed, the phenomenon of the zigzag movementof the rope R should be taken into consideration. In order to reducesuch a phenomenon, the circulating speed of the rope R and the speed ofthe ships movement should be proper, and further no change in wind andocean current, and use of pliable and flexiable rope, etc. are required.However the most basical thing is to increase the distance between tworope lines so that even when it moves zigzag on the sea-bottom, the ropetangle is not caused.

In this connection, one method is to provide a large distance ofseparation between the front guide wheel equipment 3 and rear guidewheel equipment 4 by using a very long ship or two ships. This method isvery simple and easy to carry out, however the cost for the constructionand movement of the mechanism become huge and thereby there is thepossibility of making the cost for mining metallic nodules from the deepseabottom very high.

For this purpose, this invention makes it possible to increase thedistance between two rope lines naturally by utilizing water flow. Ifthe size of the top planar plate (resistance plate) 32 of the bucket Bshown in FIG. 2 is 0.8 m in width and 1.2 m in length (about 1 m inarea), the buckets B are hanged from the rope R of mm diameter atintervals of 30 m, and the resistance factor of the rope R is 2 and thatof the bucket B is 1.4, then the thrust of about 2,000 kg per one ropeline is generated in the direction of water flow in case of 5,000 m inwater depth and 0.2 m/s in the traverse moving speed of the ship I. Onthe otherhand, if the water flow direction is at a right angle to thetop planar plate (resistance plate) 32 of each bucket B, the thrust is2.8 kg. If the plate 32 has an inclination of 30 to the water flowdirection and is arranged to cause the traverse thrust, it would bequite possible to get the thrust of about 1 kg in the directionperpendicular to the water flow and the thrust of about 2 kg in thedirection of the water flow, even if the decrease of the resistant areadue to the inclination is taken into consideration.

In case 220 buckets B are attached to one side of the rope line, thethrust of the bucket B is about 440 kg in the direction of the waterflow and that in the direction perpendicular to the water flow is about220 kg. The thrust of both the rope R and the buckets B is 2,440 kg inthe direction of the water flow, and the force in the directionperpendicular to the water flow to increase the distance between tworope lines is 220 kg. By this traverse force the rope R deflectsoutside. However, as shown in FIG. 10, if the mining ship 1 movestraverse and by that movement the water flow 42 acts on the descendingrope 9 and the buckets 13 attached to the rope 9, the deflection angle61 of the rope is assumed to be about 5. The same force acts on theascending rope 11 and the buckets 16 attached to the rope 11. However,as the buckets 16 contain metallic nodules, the rope is heavy, wherebythe deflection angle 62 of the ascending rope 11 is a little smaller andis assumed to be about 2.

If the descending rope 9 deflects by 5 and has the length of 6,600 m, itis presumed that the rope R is placed on the sea-bottom subsequently inparallel with the direction of the ship s movement 600 in outside thefall portion of the rope which does not deflect and is placed on thesea-bottom along the water flow direction. On the other hand, if thedeflection of the ascending rope 11 is 2, the rope is pulled up with aperpendicular curve from about 200 m outside the rise portion of therope which does not deflect. It means that the rope 10 at the sea-bottomand the buckets 14 attached to the rope 10 are drawn rather traverse andthe distance which the rope drags on the bottom is extremely increased.As abovementioned, if both rope lines 9 and 11 are extremely separatedfrom each other and the buckets 14 are drawn more traverse against thedirection which the rope R and the buckets B are falling to thesea-bottom, it is possible to prevent the rope R from tangling, even ifthe rope R and the buckets B move zigzag on the sea-bottom as shownpreviously in FIG. 9. Moreover as it is possible to drive the rope athigh speed, the production speed can be extremely improved.

In the method as described hereinbefore, the upper plate 32 of thebucket B is also used as a resistance plate. However it is possible toattach a suitable number of resistance plates to the rope R separatelyfrom the buckets B. FIG. 14 shows this example, in which a suitablenumber of wing-shape or hydrofoil resistance plates 82 with buoyancy areattached to the rope R (the descending part 9 is shown in the drawing)by means of a front long rope 83 and front short rope 84 fitted to aslip ring 85 at the front side and a rear long rope 86 and a rear shortrope 87 fitted to a slip ring 88 at the rear side. Meanwhile the bucketsB (13) are attached to the rope also by means of the slip rings. In thiscase the inclination against the water flow is determined by thewing-shape resistance plate 82 and the bucket B has no inclination.Namely, as shown in FIGS. 15 and 16, said suitable number of resistanceplates 82 attached to the ascending rope l1 and the descending rope 9generate thrust forces 89 and 91 in the direction of the water flow andtraverse thrust forces 90 and 92 respectively by the water flow 42.Therefore two rope lines 9 and 11 are separated from each other by theresistance plates 82. However it is preferable to hang the resistanceplates 82 from front and rear sides in parallel with the rope line asmuch as possible. Thus it is possible to decrease the change of thewater flow resistance force due to the change of the circulating speedof the rope, and thereby the horizontal water flow due to the movementof the ship 1 can mainly act. Regarding the bucket B, the top planar isa planar plate, but it may be changed. depending on the design of thebucket. The bucket is hanged from front and rear sides. That is veryeffective to hold the inclination of the resistance plate in thepreferred direction when the rope descends and ascends. However it is ahard work to fix such special buckets B (32) and resistance plates 82 tothe rope R and to remove them from it, especially it is difficult in theconventional method to treat and'drive the bucket B hanged obliquely. Inorder to solve this problem and to continuously drive the rope R, it isrequired to improve the driving unit on a ship.

' In FIG. 11, the ascending rope 11 and the buckets B (16) containingmetallic nodules pass under a guide wheel 63 and pass over a guide wheel64, and thereafter the metallic nodules contained in the buckets 16 aredropped onto the ship. Further said rope R (part 12 on the ship) passesaround guide wheels 65 and 66 and is driven with the buckets B (17)attached thereto by ball rollers 5, 6, 7 and 8. Furthermore the rope Rpasses around the outer side of guide wheels 67 and 68 and is falling tothe sea again from a guide wheel 69.

FIGS. 12 and 13 show a front view and a side view of the ball rollerrespectively. In FIG. 12, each ball 70 and 71 containing high pressureair and holding the rope 12 by facing each other is driven in therotatable manner by each speed reducing unit 72 and 73 and each motor 74and 75, and fixed on board with each holding metal 76 and 77 and asupporting frame 78 Thereby, as shown in FIG. 13, the rope 12 with thebuckets 17 hanged passes easily between each ball 70 and 71, and thedriving force is transferred to the rope 12 by the pushing pressure ofeach ball 70 and 71. The position of the rope R between the rollers 70and 71 is controlled by rollers 80 and 81.

A most important feature of this method resides in using many ballrollers placed serially for driving the mechanism for continuouslymining metallic nodules from the deep sea-bottom. The present inventorhas invented and tested some driving methods before, in which a numberof normal rope winding wheels are located serially; chain part of ropeis catched and pulled; and is pressed by oil pressure rollers totransfer the driving force. However, in the rope winding wheel system,as a bucket is turned over, there is a possibility to damage the bucket.In the oil pressure roller system, there is a defect the rope surface isdamaged. The method of catching and pulling the chain part of rope hasnot been tested yet. On the contrary, when a small size of ball rollersystem of the present invention was used in the test carried out offHawaii on Dai-ni Kyokuyo-Maru ship, the rope was not damaged and thetest proved the utility of the ball roller system.

In the present invention, as the bucket is hanged in the inclined mannerto get the efficiency of the resistance plate thereof, the bucket isdifficult to be handled and is easily damaged or transformed. By thatdamage and transformation, the resistance plate may act conversely tomake the two rope lines close to each other, whereby the rope tangle maybe caused. That rope tangle accident should not be caused at all. Forthis reason, this invention is employing a number of ball rollersarranged serially through which the buckets can pass easily without anydamage. Therefore the most effective utility can be displayed.

FIGS. 17 to 23 relate to another embodiment of the present invention, amechanism for continuously catching sea life using nets. Recently,because of exhaustion of fishery resources, many attempts for catchingnew sea life have been made. For example, in the South Pole sea, mysisesare distributed in large quantities in the wide range of sea. Once anindirect method was taken, i.e., whales which ate mysises were caught byhuman beings. Now there is a prospect that mysises are directly caughtand utilized like a shrimp. However, in the practical trial for catchingmysises, when a ship approaches shoals of mysises, they scatter, so thatonly small quantity of them are caught. Therefore the development of anew mechanism has been required.

The mechanism for continuously catching fish using nets of the presentinvention has a feature in catching effectively sea life distributed inthe wide sea of some depth.

One example embodying the present invention will be describedhereinbelow in conjunction with accompanying drawings. In FIG. 17, aship 101 has a propeller 102, a rudder 103 and a space enough to stocksea life caught, and driving ball rollers 104, 105 and 106 are providedat one end of the stern of the ship, at another end of the stern and onthe deck respectively.

In case the mechanism of this invention is operated using only one shipas above mentioned, a rope 107 has nets 108 and resistance plates 109 atcertain intervals. As rope material, any one of fiber and cable isusable. Preferably the rope is balanced on torque, but it is not anabsolute condition.

In order to effectively catch mysises living gregariously in the widesea of some depth, e.g. 20 m 50 m deep, it is preferableto scoop waterwith a number of nets at pretty high speed. For this object, it ispreferable to open the mouth of the net of the descending rope wide.

A net 108 is hanged from the rope 107 between fixing metals 146 and 147by means of a ring 111 and metal bars 112 and 113 so as to face alwaystoward the counter force without regard to the circulation of the rope.

A resistance plate 109 is hanged from the rope 107 at the positiondetermined by fixing metals 148 and 149 and 150 and 151 by means ofrings 115 and 116, metal bars 117 and 118 connected to the ringsrespectively and long bars 119 and 120 and short bars 121 and 122 havingY shape in the manner shown in FIG. 20 as observed from the ship.

The resistance plate 109 is lighter than water, and it is made of mainlypolyethylene or wood. Outside the water, the resistance plate is hangedfrom the rope 107 as shown in FIG. 19, but in the water the plate hassome inclination against the direction of the water flow 123 mainly madeby the movement of the ship. That inclination of the plate generates thetraverse thrusts 124 and 125 which are effective to separate the tworope lines from each other.

In order to drive such a rope having a loop shape and hanging manythings, ball rollers shown in FIGS. 21-and 22 are very effective.

The ball rollers 131 and 132 containing air are rotated by motors 127and 128 attached to a boom 126 through speed reducing units 129 and 130.The rope is hold between two balls by the air pressure inside the ballsand is driven. As the roller can hold the rope without any trouble evenif the rope is pulled from the lower place than usual, it is possible tohold the rope with the net 108 attached. As the above mentionedoperation is the same when the rope is drawn down to the sea and whenthe'rope is driven on the ship, the rope can be circulatedby therotation of the driving ball rollers 104, I and 106 provided on the ship101. As seen in the normal fishing technique, it is needless to say thatthe contents in the net are dropped by pulling a string 133 to open thebottom of the net and the net is falling to the sea again after thebottom is closed.

I claim:

1. A mechanism for continuously mining metallic nodules from the deepsea-bottom comprising:

an endless rope;

a ship having a bow and a stern;

a plurality of buckets attached to said rope at intervals;

driving means for circulating said rope to descend and ascend from thestern of said ship at a fixed speed;

a plurality of resistance means attached at invervals to said rope tocirculate with said rope for increasing the distance of separation ofsaid ascending and descending portions of said rope in response to thewater flow generated by the forward movement of the ship at a fixedspeed; and

a front connector means and a rear connector means for connecting saidresistance means to said rope at two points, each of said connectormeans includes a first arm connected to said resistance means at a firstpoint and to said rope and a second arm connected to said resistancemeans at a point spaced from said first point and to said rope. saidfirst arm being shorter than said second arm.

2. The mechanism of claim 1 wherein said resistance means comprises aplate having a hydrofoil crosssectional configuration.

3. The mechanism of claim 1 wherein said resistance means comprises aplanar plate forming the top of said bucket.

4. The mechanism of claim 1 wherein said first arm and said second armare connected to said rope at a single point by a third arm.

5. The mechanism of claim 1 wherein said driving means circulates saidrope at approximately the same speed as the forward speed of said ship.

6. A mechanism for continuously catching sea life distributed inrelatively wide ranges of sea comprising:

an endless rope;

a ship having a bow and a stern;

a plurality of nets attached to said rope at intervals;

driving means for circulating said rope to descend and ascend from thestern of said ship at a fixed speed;

a plurality of resistance means attached at intervals to said rope tocirculate with said rope for increasing the distance of separation ofsaid ascending and descending portions of said rope in response to thewater flow generated by the forward movement of said ship at a fixedspeed; and

a front connector means and a rear connector means for connecting saidresistance means to said rope at two points, each of said connectormeans includes a first arm connected to said resistance means at a firstpoint and to said rope and a second arm connected to said resistancemeans at a point spaced from said first point and-to said rope, saidfirst arm being shorter than said second arm.

7. The mechanism of claim 6 wherein said first arm and said second armare connected to said rope at a single point by a third arm.

8. The mechanism of claim 6 wherein said resistance means comprises aplate having a hydrofoil crosssectional configuration.

9. The mechanism of claim 6 wherein said drive means circulates saidrope at approximately the same speed as the forward speed of said ship.

1. A mechanism for continuously mining metallic nodules from the deepsea-bottom comprising: an endless rope; a ship having a bow and a stern;a plurality of buckets attached to said rope at intervals; driving meansfor circulating said rope to descend and ascend from the stern of saidship at a fixed speed; a plurality of resistance means attached atinvervals to said roPe to circulate with said rope for increasing thedistance of separation of said ascending and descending portions of saidrope in response to the water flow generated by the forward movement ofthe ship at a fixed speed; and a front connector means and a rearconnector means for connecting said resistance means to said rope at twopoints, each of said connector means includes a first arm connected tosaid resistance means at a first point and to said rope and a second armconnected to said resistance means at a point spaced from said firstpoint and to said rope, said first arm being shorter than said secondarm.
 2. The mechanism of claim 1 wherein said resistance means comprisesa plate having a hydrofoil cross-sectional configuration.
 3. Themechanism of claim 1 wherein said resistance means comprises a planarplate forming the top of said bucket.
 4. The mechanism of claim 1wherein said first arm and said second arm are connected to said rope ata single point by a third arm.
 5. The mechanism of claim 1 wherein saiddriving means circulates said rope at approximately the same speed asthe forward speed of said ship.
 6. A mechanism for continuously catchingsea life distributed in relatively wide ranges of sea comprising: anendless rope; a ship having a bow and a stern; a plurality of netsattached to said rope at intervals; driving means for circulating saidrope to descend and ascend from the stern of said ship at a fixed speed;a plurality of resistance means attached at intervals to said rope tocirculate with said rope for increasing the distance of separation ofsaid ascending and descending portions of said rope in response to thewater flow generated by the forward movement of said ship at a fixedspeed; and a front connector means and a rear connector means forconnecting said resistance means to said rope at two points, each ofsaid connector means includes a first arm connected to said resistancemeans at a first point and to said rope and a second arm connected tosaid resistance means at a point spaced from said first point and tosaid rope, said first arm being shorter than said second arm.
 7. Themechanism of claim 6 wherein said first arm and said second arm areconnected to said rope at a single point by a third arm.
 8. Themechanism of claim 6 wherein said resistance means comprises a platehaving a hydrofoil cross-sectional configuration.
 9. The mechanism ofclaim 6 wherein said drive means circulates said rope at approximatelythe same speed as the forward speed of said ship.